TPS4811-Q1: review schematic

Hi Jimmy,

The schematic looks great! Please see the following recommendations:

-CBST is too small as of now. Please use the max total gate charge (worst case scenario) for the calculations (all FETs + pre-charge FET). A sufficient BST capacitor size is critical for proper functionality. 

-It is recommended that the 48V net is placed before the TVS diode for transient protection.

-Depending on the output capacitance, please consider adding additional slew rate controls on the gates of the FETs. If you choose to add additional capacitance on the gates, you will have to recalculate the CBST capacitor to make sure it is large enough to support all of the FETs and the additional capacitive loading for inrush control.

-For the diodes on the input and output – please make sure the values are chosen correctly considering any voltage transients and/or negative voltages that the system will experience.

-An RC filter should be placed close to the VS pin to filter out noise if that is a concern.

-If you have EMI concerns, connect ferrite beads to the CS+ and CS- pins.

-Please make sure to use the TPS4811-Q1 calculator to verify your component values.

SLURB09 Calculation tool | TI.com

-Please also use the TPS4811-Q1 FET SOA calculator to verify that your FET selection works.

FET-INRUSH-SOA-CALC Calculation tool | TI.com

Thanks,

Rishika Patel